This invention relates to image processing, and more particularly to object tracking, contour prediction, and occlusion and disocclusion detection in a video sequence.
With increasing computational power, more complex operations may be performed on images, such as detecting foreground objects. Once the foreground object is located, it can be tracked through frames of a video sequence. Knowing the location of the foreground object in each frame allows video compression to be improved, since more computational resources and transmission bandwidth can be allocated to the foreground object while less is allocated for the background.
Software is desirable that detects foreground or moving objects, and draws bounding boxes or contours around the object in each frame of the video sequence. The parent application described in detail such object tracking using macroblocks. Near the boundary of the object, the macroblocks can be divided into smaller blocks to improve the tracked contour of the object. Such block-based object tracking can be performed more efficiently than other known object-tracking methods. Frames can be skipped when object motion is low, while faster object motion tracking proceeds frame-by-frame. Such tracking modulation was also described in the parent application. FIGS. 1–2 describe the modulated, block-based object tracking detailed in the parent application.